PerCellVac2

High grade gliomas are associated with poor prognosis and high mortality. Conventional treatments and management of high grade gliomas have shown little improvement in 5-year overall survival. This phase I trial evaluated the safety, immunogenicity, and potential synergy of surgical resection with Gliadel Wafer implantation, followed by autologous tumor lysate-pulsed dendritic cell (DC) vaccine in patients with malignant glioma. Primary end points of this study were safety and surrogate markers of immunogenicity, overall survival, and progression free survival. Following surgical resection, Gliadel Wafers were placed along the resection cavity. Patients subsequently received intradermal injections of autologous tumor lysate-pulsed DC vaccines 3 times at 2 week intervals. Treatment response was evaluated clinically and through MRI at regular intervals. Twenty-eight patients received Gliadel Wafers and DC vaccination: 11 newly diagnosed (8 glioblastoma [GBM], 2 anaplastic astrocytoma [AA], and 1 anaplastic oligodendroglioma [AO]) and 17 recurrent (15 GBMs, 1 AA, and 1 AO) high grade gliomas. Immunogenicity data was collected for 20 of the 28 patients. Five of 20 patients showed elevated IFN-γ responses following vaccination. Median progression-free survival and overall survival for all GBM patients in the trial from the start of vaccination were 3.6 months and 16.9 months respectively. Comparisons between vaccine responders and non-vaccine responders were not statistically significant. Adjuvant autologous dendritic cells pulsed with tumor-lysate following resection and Gliadel Wafer placement is safe, elicits modest immunogenicity and shows similar clinical outcomes in patients who had DC vaccination in previous studies.

Dendritic cell (DC) vaccines are currently one of the most effective approaches to treat melanoma. The immunogenicity of antigens loaded into DCs determines the treatment effects. Patients treated with autologous antigen-loaded DC vaccines achieve the best therapeutic effects. In China, most melanoma patients cannot access their autologous antigens because of formalin treatment of tumor tissue after surgery. In the present study, we purified heat shock protein 70 (HSP70)-peptide complexes (PCs) from human melanoma cell lines A375, A875, M21, M14, WM‑35, and SK‑HEL‑1. We named the purified product as M‑HSP70‑PCs, and determined its immunological activities. Autologous HSP70‑PCs purified from primary tumor cells of melanoma patients (nine cases) were used as controls. These two kinds of tumor antigenic complexes loaded into DCs were used to stimulate an antitumor response against tumor cells in the corresponding patients. Mature DCs pulsed with M‑HSP70‑PCs stimulated autologous T cells to secrete the same levels of type I cytokines compared with the autologous HSP70‑PCs. Moreover, DCs pulsed with M‑HSP70‑PCs induced CD8+ T cells with an equal ability to kill melanoma cells from patients compared with autologous HSP70‑PCs. Next, we used these PC‑pulsed autologous DCs and induced autologous specific CD8+ T cells to treat one patient with melanoma of the nasal skin and lung metastasis. The treatment achieved a good effect after six cycles. These findings provide a new direction for DC-based immunotherapy for melanoma patients who cannot access autologous antigens.